JP6938191B2 - Manufacturing method of resin molded products and manufacturing method of optical parts - Google Patents

Description

The present invention relates to a method for manufacturing a resin molded product and a method for manufacturing an optical component. More specifically, the present invention relates to a method of manufacturing a resin molded product by imprint molding, and a method of manufacturing an optical component using the resin molded product.

In recent years, the product value of mobile electronic devices such as mobile phones and smartphones has been improved by installing sensors and cameras. The size and thickness of the optical components such as lenses used for them are becoming smaller and thinner year by year, and there is a demand for smaller and thinner optical components. Conventionally, such demands have been met by manufacturing optical parts by injection molding, but the injection molding method has reached its limit in responding to miniaturization and thinning. Therefore, imprint molding technology is attracting attention as a new molding method instead of the injection molding method (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2010-266664

When a resin molded product having a fine shape is molded by imprint molding, the mold used is provided with a fine pattern shape (pattern shape portion) corresponding to the fine shape of the resin molded product. However, in the case where the resin molded product is molded by imprint molding using a mold having such a fine pattern shape portion, the present inventor applies the curable composition forming the resin molded product to the mold. It has been found that bubbles are likely to be generated (foam biting) in the curable composition. The above-mentioned air bubbles are particularly likely to be generated near the bottom of the concave portion of the fine pattern-shaped portion provided on the mold (the portion that becomes the tip of the convex portion of the resin molded product after molding).

Therefore, an object of the present invention is a method for producing a resin molded product in which bubbles are less likely to be generated when a curable composition is applied to a mold having a pattern-shaped portion in imprint molding, and the resin molded product is used. The purpose is to provide a method for manufacturing an optical component.

As a result of diligent studies to achieve the above object, the present inventor has made a wettability-improving treatment on the uncoated portion of the mold having a pattern-shaped portion whose surface has been subjected to the wettability-improving treatment. It has been found that by applying a curable composition having a small contact angle with respect to the mold, it is possible to make it difficult for bubbles to occur when the curable composition is applied to the pattern-shaped portion of the mold. The present invention has been completed based on these findings.

That is, the present invention is a method for producing a resin molded product by imprint molding, and the wettability is applied to a portion of a mold that has a pattern-shaped portion whose surface has been subjected to a wettability improving treatment and has not been coated with a curable composition. A curable composition coating step of applying a curable composition having a contact angle of 50 ° or less with respect to the mold before the improvement treatment, and curing of the curable composition applied to the mold to obtain a resin molded product. Provided is a method for producing a resin molded product having a process.

The wettability improving treatment is preferably one or more treatments selected from the group consisting of plasma discharge treatment, corona discharge treatment, ozone exposure treatment, and excimer treatment.

The plasma discharge treatment or the corona discharge treatment is preferably a discharge treatment having a discharge amount of 50 W · min / m ² or more.

After the curable composition coating step, the mold to which the curable composition obtained through the curable composition coating step is applied is coated with the curable composition through the curable composition coating step. It is preferable to have a mold closing step of superimposing the curable composition on the other mold so as to be in contact with each other.

The curable composition preferably contains an epoxy compound.

It is preferable to have a defoaming step under reduced pressure after the curable composition coating step.

It is preferable that the pattern shape in the mold is an uneven shape, and the height difference between the bottommost portion of the concave portion and the topmost portion of the convex portion is 0.05 mm or more.

The resin molded product is preferably a microlens array.

The present invention also provides a method for manufacturing an optical component using the resin molded product obtained by the method for manufacturing the resin molded product.

According to the method for producing a resin molded product of the present invention, it is possible to prevent the generation of air bubbles when the curable composition is applied to the pattern-shaped portion of the mold. In particular, even when a mold having a fine pattern shape portion is used, bubbles are unlikely to be generated. Therefore, a resin molded product having a fine shape can be easily manufactured with excellent shape accuracy.

It is a process drawing which shows one Embodiment of the manufacturing method of the resin molded article of this invention. It is a schematic diagram which shows an example of a Fresnel lens, (1-a) is a cross-sectional view, and (1-b) is a view seen from directly above. It is a schematic diagram which shows the angle θ formed by the lens surface 1 and the non-lens surface 2, the lens surface 1 and the reference surface 3 in the Fresnel lens cross section.

The method for producing a resin molded product of the present invention is a method for producing a resin molded product by imprint molding, and is a portion of a mold in which a curable composition has not been applied, which has a pattern-shaped portion having a wettability improving treatment on the surface. In addition, a curable composition coating step of applying a curable composition having a contact angle of 50 ° or less with respect to the mold before the wettability improving treatment, and a resin by curing the curable composition applied to the mold. It has a curing process to obtain a molded product. In addition, in this specification, the manufacturing method of the resin molded article of this invention may be simply referred to as "the manufacturing method of this invention".

As described above, the production method of the present invention is a method of producing a resin molded product by imprint molding, and a curable composition for forming the resin molded product is applied to a substrate, and the applied curable composition is applied. Other substrates are superposed so as to be sandwiched, and then the curable composition is cured to produce a resin molded product. In the manufacturing method of the present invention, a mold having a pattern-shaped portion is used as at least one substrate, and the mold having the pattern-shaped portion (hereinafter, may be simply referred to as “mold”) is cured to the pattern-shaped portion. Apply the sex composition.

(Curable composition coating process)
In the curable composition coating step, a curable composition-uncoated portion (that is, a curable composition forming a resin molded product) of a mold having a pattern-shaped portion whose surface has been subjected to a wettability improving treatment should be coated. This is a step of applying a curable composition having a contact angle with respect to the mold of 50 ° or less to a portion (a portion that has not been applied yet).

The curable composition can be applied by a known or conventional application method. Examples of the above coating include spin coating, roll coating, spray coating (spray spray), dispense coating, dip coating, inkjet coating, airbrush coating (airbrush spraying), ultrasonic coating (ultrasonic spraying), and the like. Can be mentioned.

The curable composition is a composition that cures to form a resin molded product. The curable composition has a contact angle of 50 ° or less with respect to the mold before being subjected to the wettability improving treatment. As a result, the wettability of the curable composition with respect to the mold is increased. Therefore, even when the pattern shape portion has a fine structure, when the curable composition adheres to the mold during application, the pattern is formed. The curable composition easily wets and spreads along the shape, and bubbles are less likely to be generated. The contact angle is preferably 45 ° or less, more preferably 40 ° or less. The contact angle can be measured by a known or conventional method.

The curable composition contains a curable compound (curable compound). As the curable composition, a composition used for known or conventional imprint molding can be used, and the composition is appropriately selected according to the type of the target resin molded product. Examples of the curable compound include a cationic curable compound, a radical curable compound, an anion curable compound and the like. Examples of the cationically curable compound include a compound having an epoxy group (epoxide compound), a compound having an oxetanyl group (oxetan compound), and a compound having a vinyl ether group (vinyl ether compound), and an epoxy compound is preferable. As the curable compound, only one kind may be used, or two or more kinds may be used.

As the epoxy compound, a known or commonly used compound having one or more epoxy groups (oxylan rings) in the molecule can be used, and is not particularly limited, but for example, an alicyclic epoxy compound (alicyclic epoxy resin). ), Aromatic epoxy compound (aromatic epoxy resin), aliphatic epoxy compound (aliphatic epoxy resin) and the like.

Examples of the alicyclic epoxy compound include known and commonly used compounds having one or more alicyclics and one or more epoxy groups in the molecule, and are not particularly limited. For example, (1) in the molecule. A compound having an epoxy group (referred to as "alicyclic epoxy group") composed of two adjacent carbon atoms and oxygen atoms constituting the alicyclic; (2) The epoxy group is directly bonded to the alicyclic by a single bond. Compounds; (3) Compounds having an alicyclic ring and a glycidyl ether group in the molecule (glycidyl ether type epoxy compound) and the like can be mentioned.

Examples of the compound (1) having an alicyclic epoxy group in the molecule include a compound represented by the following formula (i).

In the above formula (i), Y represents a single bond or a linking group (a divalent group having one or more atoms). Examples of the linking group include a divalent hydrocarbon group, an alkenylene group in which part or all of the carbon-carbon double bond is epoxidized, a carbonyl group, an ether bond, an ester bond, a carbonate group, an amide group, and the like. Examples thereof include a group in which a plurality of groups are linked. A substituent such as an alkyl group may be bonded to one or more of the carbon atoms constituting the cyclohexane ring (cyclohexene oxide group) in the formula (i).

Examples of the divalent hydrocarbon group include a linear or branched alkylene group having 1 to 18 carbon atoms, a divalent alicyclic hydrocarbon group and the like. Examples of the linear or branched alkylene group having 1 to 18 carbon atoms include a methylene group, a methylmethylene group, a dimethylmethylene group, an ethylene group, a propylene group and a trimethylene group. Examples of the divalent alicyclic hydrocarbon group include 1,2-cyclopentylene group, 1,3-cyclopentylene group, cyclopentylidene group, 1,2-cyclohexylene group and 1,3-. Examples thereof include a divalent cycloalkylene group (including a cycloalkylidene group) such as a cyclohexylene group, a 1,4-cyclohexylene group and a cyclohexylidene group.

Examples of the alkenylene group in the alkenylene group in which a part or all of the carbon-carbon double bond is epoxidized (sometimes referred to as “epoxidized alkenylene group”) include a vinylene group, a propenylene group, and a 1-butenylene group. , 2-Butenylene group, butazienylene group, pentenylene group, hexenylene group, heptenylene group, octenylene group and the like, such as a linear or branched alkenylene group having 2 to 8 carbon atoms. In particular, as the epoxidized alkenylene group, an alkenylene group in which the entire carbon-carbon double bond is epoxidized is preferable, and more preferably, the entire carbon-carbon double bond is epoxidized and has 2 to 4 carbon atoms. It is an alkenylene group.

Typical examples of the alicyclic epoxy compound represented by the above formula (i) are (3,4,3', 4'-diepoxy) bicyclohexyl, and the following formulas (i-1) to (i-10). ), And the like. In addition, l and m in the following formulas (i-5) and (i-7) represent integers of 1 to 30, respectively. R'in the following formula (i-5) is an alkylene group having 1 to 8 carbon atoms, and among them, a linear or branched chain having 1 to 3 carbon atoms such as a methylene group, an ethylene group, a propylene group and an isopropylene group. The shape of the alkylene group is preferable. N1 to n6 in the following formulas (i-9) and (i-10) represent integers of 1 to 30, respectively. Examples of the alicyclic epoxy compound represented by the above formula (i) include 2,2-bis (3,4-epoxycyclohexyl) propane and 1,2-bis (3,4-epoxycyclohexane). Examples thereof include -1-yl) ethane, 1,2-epoxy-1,2-bis (3,4-epoxycyclohexane-1-yl) ethane, and bis (3,4-epoxycyclohexylmethyl) ether.

Examples of the compound in which the epoxy group is directly bonded to the alicyclic (2) by a single bond include a compound represented by the following formula (ii).

In formula (ii), R "is a group (p-valent organic group) obtained by removing p hydroxyl groups (-OH) from the structural formula of a p-valent alcohol, and p and n each represent a natural number. Examples of the valent alcohol [R "(OH) _p ] include polyhydric alcohols such as 2,2-bis (hydroxymethyl) -1-butanol (alcohols having 1 to 15 carbon atoms) and the like. p is preferably 1 to 6, and n is preferably 1 to 30. When p is 2 or more, n in each group in parentheses (in parentheses on the outside) may be the same or different. Specific examples of the compound represented by the above formula (ii) include 1,2-epoxy-4- (2-oxylanyl) cyclohexane adducts of 2,2-bis (hydroxymethyl) -1-butanol [for example. , Product name "EHPE3150" (manufactured by Daicel Corporation), etc.] and the like.

Examples of the compound having an alicyclic and glycidyl ether group in the molecule (3) described above include glycidyl ether of an alicyclic alcohol (particularly, an alicyclic polyhydric alcohol). More specifically, for example, 2,2-bis [4- (2,3-epoxypropoxy) cyclohexyl] propane, 2,2-bis [3,5-dimethyl-4- (2,3-epoxypropoxy)). Cyclohexyl] A compound obtained by hydrogenating a bisphenol A type epoxy compound such as propane (hydrogenated bisphenol A type epoxy compound); bis [o, o- (2,3-epoxypropoxy) cyclohexyl] methane, bis [o , P- (2,3-epoxypropoxy) cyclohexyl] methane, bis [p, p- (2,3-epoxypropoxy) cyclohexyl] methane, bis [3,5-dimethyl-4- (2,5-dimethylpropoxy) 3-Epoxypropoxy) Cyclohexyl] A compound obtained by hydrogenating a bisphenol F-type epoxy compound such as methane (hydrogenated bisphenol F-type epoxy compound); a hydrogenated biphenol-type epoxy compound; a hydrogenated phenol novolac-type epoxy compound; Novolak type epoxy compound; bisphenol A hydride cresol novolak type epoxy compound; hydride naphthalene type epoxy compound; hydride epoxy compound of epoxy compound obtained from trisphenol methane; hydride epoxy compound of the following aromatic epoxy compound and the like. Be done.

Examples of the aromatic epoxy compound include epibis-type glycidyl ether-type epoxy resins obtained by a condensation reaction between bisphenols [for example, bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, etc.] and epihalohydrin; these epis. High molecular weight epibistype glycidyl ether type epoxy resin obtained by further addition reaction of bistype glycidyl ether type epoxy resin with the above bisphenols; phenols [for example, phenol, cresol, xylenol, resorcin, catechol, bisphenol A, bisphenol F, bisphenol S, etc.] and aldehydes [for example, formaldehyde, acetaldehyde, benzaldehyde, hydroxybenzaldehyde, salicylaldehyde, etc.] and polyhydric alcohols obtained by condensing reaction with epihalohydrin. Alkyl type glycidyl ether type epoxy resin; Two phenol skeletons are bonded to the 9-position of the fluorene ring, and glycidyl is attached to the oxygen atom obtained by removing the hydrogen atom from the hydroxy group of these phenol skeletons, either directly or via an alkyleneoxy group. Examples thereof include an epoxy compound to which a group is bonded.

Examples of the aliphatic epoxy compound include glycidyl ethers of alcohols having no q-valent cyclic structure (q is a natural number); monovalent or polyvalent carboxylic acids [for example, acetic acid, propionic acid, butyric acid, stearic acid, etc. Glycidyl ester of adipic acid, sebacic acid, maleic acid, itaconic acid, etc.; epoxidized fats and oils with double bonds such as epoxidized flaxseed oil, epoxidized soybean oil, epoxidized castor oil; polyolefin (poly) such as epoxidized polybutadiene (Including alkaziene) epoxides and the like can be mentioned. Examples of the alcohol having no q-valent cyclic structure include monohydric alcohols such as methanol, ethanol, 1-propyl alcohol, isopropyl alcohol and 1-butanol; ethylene glycol, 1,2-propanediol, 1 , 3-Propanediol, 1,4-Butanediol, Neopentyl glycol, 1,6-hexanediol, Diethylene glycol, Triethylene glycol, Tetraethylene glycol, Dipropylene glycol, Polyethylene glycol, Polypropylene glycol and other dihydric alcohols; Examples thereof include trihydric or higher polyhydric alcohols such as glycerin, diglycerin, erythritol, trimethylolethane, trimethylolpropane, pentaerythritol, dipentaerythritol and sorbitol. Further, the q-valent alcohol may be a polyether polyol, a polyester polyol, a polycarbonate polyol, a polyolefin polyol or the like.

Examples of the oxetane compound include known and commonly used compounds having one or more oxetane rings in the molecule, and are not particularly limited. For example, 3,3-bis (vinyloxymethyl) oxetane, 3-ethyl-3-3. (Hydroxymethyl) oxetane, 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane, 3-ethyl-3-[(phenoxy) methyl] oxetane, 3-ethyl-3- (hexyloxymethyl) oxetane, 3- Ethyl-3- (chloromethyl) oxetane, 3,3-bis (chloromethyl) oxetane, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, bis {[1-ethyl (3-ethyl (3-ethyl) Oxetane)] methyl} ether, 4,4'-bis [(3-ethyl-3-oxetanyl) methoxymethyl] bicyclohexyl, 1,4-bis [(3-ethyl-3-oxetanyl) methoxymethyl] cyclohexane, 1 , 4-Bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene, 3-ethyl-3-{[(3-ethyloxetane-3-yl) methoxy] methyl)} oxetane, xylylene bisoxetane , 3-Ethyl-3-{[3- (triethoxysilyl) propoxy] methyl} oxetane, oxetanylsilsesquioxane, phenol novolac oxetane and the like.

As the vinyl ether compound, a known or commonly used compound having one or more vinyl ether groups in the molecule can be used, and is not particularly limited, but for example, 2-hydroxyethyl vinyl ether (ethylene glycol monovinyl ether), 3-hydroxy. Propyl vinyl ether, 2-hydroxypropyl vinyl ether, 2-hydroxyisopropyl vinyl ether, 4-hydroxybutyl vinyl ether, 3-hydroxybutyl vinyl ether, 2-hydroxybutyl vinyl ether, 3-hydroxyisobutylvinyl ether, 2-hydroxyisobutylvinyl ether, 1-methyl-3 -Hydroxypropyl vinyl ether, 1-methyl-2-hydroxypropyl vinyl ether, 1-hydroxymethylpropyl vinyl ether, 4-hydroxycyclohexylvinyl ether, 1,6-hexanediol monovinyl ether, 1,6-hexanediol divinyl ether, 1,8- Octanediol divinyl ether, 1,4-cyclohexanedimethanol monovinyl ether, 1,4-cyclohexanedimethanol divinyl ether, 1,3-cyclohexanedimethanol monovinyl ether, 1,3-cyclohexanedimethanol divinyl ether, 1,2-cyclohexane Dimethanol monovinyl ether, 1,2-cyclohexanedimethanol divinyl ether, p-xylene glycol monovinyl ether, p-xylene glycol divinyl ether, m-xylene glycol monovinyl ether, m-xylene glycol divinyl ether, o-xylene glycol monovinyl ether, o-xylene glycol divinyl ether, ethylene glycol divinyl ether, diethylene glycol monovinyl ether, diethylene glycol divinyl ether, triethylene glycol monovinyl ether, triethylene glycol divinyl ether, tetraethylene glycol monovinyl ether, tetraethylene glycol divinyl ether, pentaethylene glycol monovinyl ether, Pentaethylene glycol divinyl ether, oligoethylene glycol monovinyl ether, oligoethylene glycol divinyl ether, polyethylene glycol monovinyl ether, polyethylene glycol divinyl ether, dipropylene glycol monovinyl ether, dipropylene grease Cole divinyl ether, tripropylene glycol monovinyl ether, tripropylene glycol divinyl ether, tetrapropylene glycol monovinyl ether, tetrapropylene glycol divinyl ether, pentapropylene glycol monovinyl ether, pentapropylene glycol divinyl ether, oligopropylene glycol monovinyl ether, oligopropylene glycol di Vinyl ether, polypropylene glycol monovinyl ether, polypropylene glycol divinyl ether, isosorbide divinyl ether, oxanolborne divinyl ether, phenylvinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, octyl vinyl ether, cyclohexyl vinyl ether, hydroquinone divinyl ether, 1,4-butanediol Divinyl ether, cyclohexanedimethanol divinyl ether, trimethylolpropane divinyl ether, trimethylolpropanetrivinyl ether, bisphenol A divinyl ether, bisphenol F divinyl ether, hydroxyoxanorbornane methanol divinyl ether, 1,4-cyclohexanediol divinyl ether, pentaerythritol tri Examples thereof include vinyl ether, pentaerythritol tetravinyl ether, dipentaerythritol pentavinyl ether, dipentaerythritol hexavinyl ether and the like.

The content of the curable compound (particularly the epoxy compound) in the curable composition is not particularly limited, but is preferably 10 to 95% by weight, more preferably 10% by weight, based on the total amount (100% by weight) of the curable composition. It is preferably 15 to 90% by weight, more preferably 20 to 85% by weight. When the content is 10% by weight or more, the curable composition tends to be excellent in curability, heat resistance of the resin molded product, light resistance, and transparency.

The curable composition preferably contains a photopolymerization initiator together with the curable compound, and particularly preferably contains a photocationic polymerization initiator. The photocationic polymerization initiator is a compound that generates an acid by irradiation with light to initiate a curing reaction of a curable compound (particularly, a cationically curable compound) contained in a curable composition, and is a cation that absorbs light. It consists of a part and an anion part that is a source of acid.

Examples of the photocationic polymerization initiator include diazonium salt compounds, iodonium salt compounds, sulfonium salt compounds, phosphonium salt compounds, selenium salt compounds, oxonium salt compounds, ammonium salt compounds, and bromine salt compounds. And so on. In the present invention, it is particularly preferable to use a sulfonium salt-based compound in that a resin molded product having excellent curability can be formed.

Examples of the cation portion of the sulfonium salt-based compound include triphenylsulfonium ion, diphenyl [4- (phenylthio) phenyl] sulfonium ion, tri-p-tolylsulfonium ion, and (4-hydroxyphenyl) methylbenzylsulfonium ion, 4 -(4-Bifenirylthio) phenyl-4-biphenylylphenylsulfonium ion and other aryl sulfonium ions (particularly, triarylsulfonium ions) can be mentioned.

Examples of the anion portion include [(X) _s B (Phf) _4-s ] ^- (in the formula, X represents a phenyl group or a biphenylyl group. Phf has at least one hydrogen atom of a perfluoroalkyl group. perfluoroalkoxy group, and .s indicating at least one substituted phenyl group selected from the group consisting of halogen atoms is an integer of ^{_{0~3), BF 4 -, [}} (Rf) n PF 6- _n] ^- (Rf: alkyl group in which at least 80% are substituted with fluorine atoms of the hydrogen atom, n: 0 to 5 ^{_{integer), AsF 6 -, SbF 6}} -, pentafluoro-hydroxy antimonate and the like.

Examples of the photocationic polymerization initiator include (4-hydroxyphenyl) methylbenzylsulfonium tetrakis (pentafluorophenyl) borate and 4- (4-biphenylylthio) phenyl-4-biphenylylphenylsulfonium tetrakis (pentafluorophenyl). ) Borate, 4- (Phenylthio) Phenyldiphenylsulfonium Phenyltris (Pentafluorophenyl) Borate, [4- (4-Bifenirylthio) Phenyl] -4-Bifenirylphenylsulfonium Phenyltris (Pentafluorophenyl) Borate, Diphenyl [ 4- (Phenylthio) phenyl] sulfonium tris (pentafluoroethyl) trifluorophosphate, diphenyl [4- (phenylthio) phenyl] sulfonium tetrakis (pentafluorophenyl) borate, diphenyl [4- (phenylthio) phenyl] sulfonium hexafluorophosphate, 4- (4-Biphenylylthio) phenyl-4-biphenylylphenylsulfonium Tris (pentafluoroethyl) trifluorophosphate, bis [4- (diphenylsulfonio) phenyl] sulfide phenyltris (pentafluorophenyl) borate, [4 -(2-Thioxanthonylthio) phenyl] Phenyl-2-thioxanthonyl sulfonium Phenyltris (pentafluorophenyl) borate, trade names "Cyracure UVI-6970", "Cyracure UVI-6974", "Cyracure UVI-6990" , "Cyracure UVI-950" (above, manufactured by Union Carbide, USA), "Irgacure 250", "Irgacure 261", "Irgacure 264" (above, manufactured by Ciba Specialty Chemicals), "SP-150", " "SP-151", "SP-170", "Optomer SP-171" (above, manufactured by ADEKA Co., Ltd.), "CG-24-61" (manufactured by Ciba Specialty Chemicals), "DAICAT II" ((() (Manufactured by Daicel Co., Ltd.), "UVAC1590", "UVAC1591" (all manufactured by Daicel Cytec Co., Ltd.), "CI-2064", "CI-2339", "CI-2624", "CI-2481", " "CI-2734", "CI-2855", "CI-2823", "CI-2758", "CIT-1682" (all manufactured by Nippon Soda Co., Ltd.), "PI-" 2074 "(Rodia, tetrakis (pentafluorophenylbolate) toluyl cumyliodonium salt)," FFC509 "(3M)," BBI-102 "," BBI-101 "," BBI-103 "," MPI -103 "," TPS-103 "," MDS-103 "," DTS-103 "," NAT-103 "," NDS-103 "(all manufactured by Midori Chemical Co., Ltd.)," CD-1010 ", Commercially available products such as "CD-1011", "CD-1012" (above, manufactured by Saltomer, USA), "CPI-100P", "CPI-101A", "CPI-200K" (above, manufactured by Sun Appro Co., Ltd.), etc. Goods can be used.

As the photopolymerization initiator, only one kind may be used, or two or more kinds may be used. The amount used (blended amount) is preferably 0.01 to 15 parts by weight, more preferably 0.05, based on 100 parts by weight of the curable compound (particularly, the cationically curable compound) contained in the curable composition. It is 10 parts by weight, more preferably 0.1 to 5 parts by weight. By using the photopolymerization initiator within the above range, a resin molded product having excellent curability, heat resistance, light resistance, transparency, optical properties and the like can be obtained.

The curable composition comprises the curable compound, the photopolymerization initiator, and, if necessary, other components (eg, solvent, antioxidant, photosensitizer, defoaming agent, leveling agent, coupling agent). , Surfactant, flame retardant, ultraviolet absorber, colorant, etc.) may be contained. As the curable composition, for example, a commercially available product such as the trade name "CELVENUS OUH106" (manufactured by Daicel Corporation) can be used.

The mold is provided with an inverted uneven pattern shape (inverted shape of the desired resin molded product) corresponding to the desired shape to give the resin molded product a desired shape. The mold may have a contact angle of 50 ° or less with respect to the mold of the curable composition forming the resin molded product, but is preferably made of resin. The resin forming the mold is selected in consideration of the contact angle of the curable composition, the peelability of the resin molded product after curing, and the like. For example, a silicone-based resin (dimethylpolysiloxane, etc.), a fluorine-based resin, etc. , Polyethylene resin (polyethylene, polypropylene, polycyclic olefin, etc.), polyether sulfone resin, polycarbonate resin, polyester resin (polyarylate, polyethylene terephthalate, polyethylene naphthalate, etc.), polyamide resin, polymethyl methacrylate, etc. Can be mentioned. Among the above resins, silicone-based resins are preferable. When a silicone-based resin is used, it is excellent in compatibility with a curable composition containing an epoxy compound, and the contact angle tends to be small. In addition, since the resin molded product is excellent in releasability and mold flexibility, the resin molded product can be taken out more easily.

In the above mold, the surface of the pattern shape portion is subjected to a wettability improving treatment. As the wettability improving treatment, plasma discharge treatment, corona discharge treatment, ozone exposure treatment, and excimer treatment are preferable, and plasma discharge treatment and corona discharge treatment are more preferable. By applying these wettability improving treatments to the mold, the wettability of the curable composition is improved. Then, by combining with the use of the curable composition having the contact angle of 50 ° or less, the compatibility between the curable composition and the mold is further improved, and the fine pattern shape portion formed on the mold is further improved. The curable composition easily reaches the tip of the concave portion of the above, and the generation of air bubbles can be suppressed.

The plasma discharge process is a process of processing the mold surface by generating positive and negative charged particles activated by discharging in the atmosphere. The corona discharge process is a process of processing the mold surface by generating a non-uniform electric field around a sharp electrode (needle electrode) and generating a continuous discharge. The ozone exposure treatment is, for example, a treatment for processing the mold surface by generating ozone by irradiating ultraviolet rays using a low-pressure mercury lamp or the like in the presence of oxygen. The excimer treatment is a process of processing the mold surface by ultraviolet irradiation or laser irradiation using an excimer lamp in a vacuum state.

In the plasma discharge treatment or the corona discharge treatment, the discharge amount ^{is preferably 50 W · min / m 2} or more, and more preferably 80 W · min / m ² or more, although it is not particularly limited. When the amount of discharge is 50 W · min / m ² or more, the wettability of the curable composition is further improved, and the generation of bubbles is less likely to occur after coating.

As the mold, a commercially available product may be used, or a manufactured product may be used. When manufacturing a mold, for example, the resin composition forming the mold is molded (preferably imprinted), heat-cured, and then the surface of the pattern-shaped portion of the mold is subjected to a wettability improving treatment. Can be done. A mold having an uneven shape can be used for molding the resin composition, and for example, it can be produced by the methods (1) and (2) below.
(1) A method in which a mold is pressed against a coating film of a resin composition applied on a substrate to cure the coating film of the resin composition, and then the mold is peeled off. (2) The resin composition is applied to the mold. A method in which an object is directly coated, a substrate is brought into close contact with the object, the coating film of the resin composition is cured, and then the mold is peeled off.

In the above mold, a mold release agent may be applied to at least a part of the pattern shape portion. If the mold release agent is applied to the mold before the curable composition is applied, the formed resin molded product can be easily released when it is taken out (removed) from the mold. In this case, since the release layer is usually released from the mold at the same time, the obtained resin molded product has at least one release layer on the surface.

Examples of the release agent include a fluorine-based release agent, a silicone-based release agent, a wax-based release agent, and the like. As the release agent, one kind may be used, or two or more kinds may be used. Examples of the method for applying the release agent include a spray method, a spin coating method, and a screen printing method.

As described above, in the curable composition coating step, a mold is obtained in which the curable composition is coated (filled) on the pattern-shaped portion whose surface is subjected to the wettability improving treatment.

(Defoaming process)
The production method of the present invention may include a step (defoaming step) of defoaming bubbles in the applied curable composition after the curable composition coating step. In the production method of the present invention, the generation of air bubbles in the curable composition is considerably suppressed in the curable composition coating step, but the slightly generated air bubbles can be removed by the defoaming step.

The defoaming can be performed by a known or conventional defoaming method, and defoaming by decompression (decompression defoaming, vacuum defoaming) is preferable. The decompression defoaming can be performed, for example, by allowing the mold filled with the curable composition to stand in an environment of a pressure of 0.1 to 20 kPa for 1 to 10 minutes.

(Mold closing process)
A mold to which the curable composition is applied (filled) obtained through the curable composition coating step (if necessary, a defoaming step) is sandwiched between the applied curable composition and another. Perform the process of stacking with the substrate (mold closing process). That is, the mold coated with the curable composition and the other substrate are used as the upper mold and the lower mold, respectively, and the mold closing steps of the upper mold and the lower mold are performed so as to sandwich the curable composition. .. At this time, whichever is the upper mold or the lower mold may be used.

The other substrate may be a mold having a pattern-shaped portion (another mold different from the mold used in the above-mentioned curable composition coating step), and a substrate having no pattern-shaped portion (flat substrate). It may be. For example, when manufacturing a resin molded product having an uneven shape on only one surface, the flat substrate can be used as the other substrate, and when producing a resin molded product having an uneven shape on both sides, the above other substrate can be used. The other molds described above can be used as the substrate.

As the other mold, the same mold as the one subjected to the above-mentioned wettability improving treatment can be used. The above two molds may be made of different materials or may be made of the same material. Further, the above two molds may have the same pattern shape portion or may have different pattern shape portions.

Examples of the flat substrate include a glass plate; a semiconductor such as silicon, gallium arsenide, and gallium nitride; a resin substrate such as polycarbonate, polypropylene, and polyethylene; a metal substrate; and a combination of these materials. The flat substrate may have a pattern structure such as a fine wiring, a crystal structure, an optical waveguide, and an optical structure such as holography.

The curable composition may or may not be applied to the other substrate. When the curable composition is applied to the other substrate, the curable composition coating step (if necessary, a defoaming step) using a mold having a pattern-shaped portion whose surface has been subjected to a wettability improving treatment. ), And a mold coated (filled) with the curable composition may be used. Therefore, when a resin molded product having an uneven shape on both sides is manufactured, the mold as the other substrate is the above-mentioned curable composition coating step using a mold having a pattern-shaped portion whose surface is subjected to a wettability improving treatment. It is preferable to use a mold filled with the curable composition after undergoing (if necessary, a defoaming step). As the other substrate, the curable composition is coated on a substrate (particularly, the curable composition is subjected to the above-mentioned curable composition coating step using a mold having a pattern-shaped portion having a wettability improving treatment on the surface). When a coated mold) is used, the mold closing step superimposes the upper mold and the lower mold so that the curable compositions are in contact with each other.

(Press process)
The manufacturing method of the present invention may include a step (pressing step) of pressing from the upper part of the upper mold after the mold closing step. Thereby, the thickness variation of the obtained resin molded product can be reduced. The pressure at the time of pressing is, for example, 0.01 to 100 MPa.

(Curing process)
In the curing step, the curable composition applied (filled) to the mold is cured to obtain a resin molded product. Specifically, the curable composition can be cured by advancing the polymerization reaction of the curable compound (particularly, the cationic curable compound) contained in the curable composition. The curing method can be appropriately selected from well-known or conventional methods, and is not particularly limited, and examples thereof include a method of irradiating with active energy rays and / or heating. As the active energy ray, for example, any of infrared rays, visible rays, ultraviolet rays, X-rays, electron beams, α rays, β rays, γ rays and the like can be used. Of these, ultraviolet rays are preferable because they are easy to handle.

As a light source for irradiating ultraviolet rays, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, or the like is used. The irradiation time varies depending on the type of light source, the distance between the light source and the coated surface, and other conditions, but is several tens of seconds at the longest. The illuminance is, for example, about 5 to 200 mW. After irradiation with active energy rays, heating (post-cure) may be performed as necessary to promote curing.

Through the above curing step, the curable composition is cured, and a resin molded product can be obtained. After the curing step, the upper mold and the lower mold can be opened, and the resin molded product can be taken out from the mold.

FIG. 1 is a process diagram showing an embodiment of the manufacturing method of the present invention. In the production method of the present invention shown in FIG. 1, a contact angle with respect to the mold before the wettability improving treatment is formed on a portion of a mold having a pattern-shaped portion whose surface has been subjected to a wettability improving treatment and which has not been coated with the curable composition. A curable composition coating step S1 for applying a curable composition having a temperature of 50 ° or less, a defoaming step S2 for defoaming bubbles in the applied curable composition, and the curable composition being coated (filled). The mold closing step S3 in which the mold is superposed on another substrate so as to sandwich the applied curable composition, the pressing step S4 in which the mold is pressed from the upper part of the upper mold, and the curable composition applied to the mold are cured. The curing step S5 for obtaining a resin molded product is provided in this order.

The resin molded product obtained by the manufacturing method of the present invention includes, for example, a lens, a prism, an LED, an organic EL element, a semiconductor laser, a transistor, a solar cell, a CCD image sensor, an optical waveguide, an optical fiber, and a substitute glass (for example, a substrate for a display). , Hard disk substrate, polarizing film) and the like.

As the optical component, for example, when manufacturing a lens, it may be obtained as a microlens array [for example, a structure having a shape in which a plurality of microlenses are arranged in a matrix in the vertical and horizontal directions]. That is, it is preferable that the mold has a pattern shape corresponding to the shape of the microlens array.

As for the size of the optical component, for example, when the optical component is a microlens array, the size of one microlens is, for example, about 0.01 to 100 mm in diameter and about 0.1 to 2.0 mm in thickness. The pitch width of the microlens array is, for example, about 10 to 1000 μm.

The optical component is particularly preferably a Fresnel lens array. As shown in FIG. 2, the Fresnel lens is a prism composed of a lens surface 1 on the surface and a non-lens surface 2 facing the lens surface, and has a plurality of prisms having a chevron-shaped cross section. It is a formed lens. The angle θ formed by the lens surface 1 and the reference surface 3 continuously decreases (or increases) toward the center, and when only the lens surface 1 is continuous, one convex lens (or concave lens) is formed. Form (see FIG. 3). As shown in FIGS. 2 and 3, the mold for molding the Fresnel lens array has a fine uneven shape, so that bubbles are particularly likely to be generated when the curable composition is applied. However, the method for producing a resin molded product of the present invention can suppress the generation of air bubbles during coating even for a mold for producing a resin molded product having a particularly fine uneven shape such as a Fresnel lens array. can.

The repetition interval (distance between the top of the convex portion or the deepest portion of the concave portion, that is, the pitch width of the prism shape) in the Fresnel lens array is not particularly limited, but is preferably 0.5 mm or less, more preferably 0.2 mm or less. More preferably, it is 0.1 mm or less. The lower limit is, for example, 0.05 mm. The narrower the repetition interval, the more difficult it is to prevent the generation of bubbles. However, according to the method for producing a resin molded product of the present invention, the generation of bubbles during coating even for a mold corresponding to such a repetition interval. Can be suppressed.

The sharpness (the tip R of the convex portion or the valley R of the concave portion, that is, the sharpness of the sharpness angle / cutting angle) in the Fresnel lens array is not particularly limited, but is preferably R0.01 mm or less, more preferably R0.005 mm or less. More preferably, it is R0.001 mm or less. The lower limit is, for example, 0.0005 mm. The smaller the R, the more difficult it is to prevent the generation of bubbles. However, according to the method for producing a resin molded product of the present invention, the generation of bubbles during coating can be generated even in a mold corresponding to such sharpness. It can be suppressed.

The height interval (height difference between the top of the convex portion and the deepest portion of the concave portion) in the Fresnel lens array is not particularly limited, but is preferably 0.05 mm or more, more preferably 0.5 mm or more, still more preferably 5 mm or more. .. The upper limit is, for example, 10 mm. The higher the height interval, the more difficult it is to prevent the generation of air bubbles. However, according to the method for producing a resin molded product of the present invention, air bubbles at the time of coating can be applied to a mold corresponding to such a height interval. Can be suppressed.

S1 Curable composition coating process S2 Defoaming process S3 Mold closing process S4 Pressing process S5 Curing process

Claims (7)

A method of manufacturing a resin molded product by imprint molding, in which the mold before the wettability improving treatment is applied to a portion of a mold having a pattern-shaped portion whose surface has been subjected to a wettability improving treatment. Resin molding, which comprises a curable composition coating step of applying a curable composition having a contact angle of 50 ° or less with respect to the mold, and a curing step of curing the curable composition applied to the mold to obtain a resin molded product. It is a manufacturing method of goods
The curable composition is a curable composition containing an epoxy compound.
The mold is a silicone-based resin mold.
A method for producing a resin molded product, wherein the wettability improving treatment is one or more treatments selected from the group consisting of plasma discharge treatment, corona discharge treatment, ozone exposure treatment, and excimer treatment. The method for producing a resin molded product according to claim 1, wherein the plasma discharge treatment or the corona discharge treatment is a discharge treatment having a discharge amount of 50 W · min / m ^{2 or more.} After the curable composition coating step, the mold to which the curable composition obtained through the curable composition coating step is applied is coated with the curable composition through the curable composition coating step. The method for producing a resin molded product according to claim 1 or 2, further comprising a mold closing step of superimposing the curable composition on another mold so as to be in contact with each other. The method for producing a resin molded product according to any one of claims 1 to 3 , further comprising a defoaming step by reducing pressure after the curable composition coating step. The method for producing a resin molded product according to any one of claims 1 to 4 , wherein the pattern shape in the mold is an uneven shape, and the height difference between the bottom of the concave portion and the top of the convex portion is 0.05 mm or more. The method for producing a resin molded product according to any one of claims 1 to 5 , wherein the resin molded product is a microlens array. A method for manufacturing an optical component using a resin molded product obtained by the method for manufacturing a resin molded product according to any one of claims 1 to 6.

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